1. Field of the Invention
The present invention relates to a distributed diagnostic system with a single diagnostic protocol server and multiple data source modules for internal combustion engines.
The present invention further relates to an Engine Control Unit comprised of at least two modules, namely a Common Powertrain Controller (CPC2) and a Motor Control Module (MCM) in electronic communication with each other. Each module is located with compatible, minimum version of software to enable the CPC2 to understand diagnostic trouble codes (DTC) from the MCM without the necessity of translating the CMC DTC's to CPC2 DTC.
The present invention is further related to a CPC2/CMC diagnostic system in which a single module (CPC2) has a rate of a diagnostic gateway (i.e., it is the only module communicating diagnostic information and SAE data links) while the other module (MCM or equivalent) communicates a reduced set of diagnostic information to the gateway module (CPC2) which then interprets and expands the information before making it available on the SAE links. This approach ensures that a time gap of no more than 1 to 2 seconds exists from failure detection on a remote data source module to the actual failure reporting from a gateway module.
2. Description of the Related Art
Berstis, et al. U.S. Pat. No. 6,549,972 discloses a method for providing control access between a device on a non-proprietary bus and a device on a proprietary bus. A gateway controller is connected between a proprietary bus and a non-proprietary bus. A message originated from a device on the non-proprietary bus intended for a device on the proprietary bus is checked by the gateway controller to determine if a transmission of the message should be permitted according to a permitted message bitmap. The permitted message bitmap contains a list of devices on the non-proprietary bus that are previously registered as able to communicate with devices on the proprietary bus and a list of permitted messages associated with each of the devices on the non-proprietary bus. The transmission of the message to the device on the proprietary bus is denied if the message is not registered within the permitted message bitmap.
Berstis, et al., U.S. Pat. No. 6,823,457 is a method for verifying control accesses between a device on a non-proprietary bus and a device on a proprietary bus. A gateway controller is connected between a proprietary bus and a non-proprietary bus. A determination is made as to whether or not a non-proprietary device is registered to more than one gateway controller. In response to a determination that the non-proprietary device is registered to more than one gateway controller, another determination is made as to whether or not the non-proprietary device is a portable device. In response to a determination that the non-proprietary device is a portable device, another determination is made as to whether or not a number of acceptable duplication has been exceeded. In response to a determination that the number of acceptable duplication has been exceeded, a flag is set to indicate a control access violation has occurred.
Pellegrino, et al. U.S. Publication No. 2002/0161820 discloses a computer implemented translation system that provides a programming interface between a client and a remote device that is connected to a vehicle data network. The translation device presents programmers with a uniform extraction of vehicle networks that permits programming and diagnostic procedures to be carried out without reference by the programmer to nuances of the particular network class used and on the motor vehicle. Three major interfaces are defined to implement the invention. The network interface incorporates a plurality of functions representing a model of a physical network. A data link interface responsive to client request requiring a network instance corresponding to a physical network from the network interface. The establishment of a network instance may involve reference to a database to obtain appropriate drivers for the underlying physical network represented by the network instance. A remote device interface incorporates a plurality of functions representing the physical devices capable through the network interface and handles messages between the client and the physical device attached to the underlying physical network.